Hollow piece for producing a sintered refractory product exhibiting improved bubbling behaviour

Abstract

A green part, a region of a refractory furnace or a hollow piece for producing a sintered refractory has the following mean mineral chemical composition in weight percent based of mineral oxides: 40%≦Al 2 O 3 ≦94%, 0%≦ZrO 2 ≦41%, 2%≦SiO 2 ≦22%, 1%<Y 2 O 3 +V 2 O 5 +TiO 2 +Sb 2 O 3 +Yb 2 O 3 +Na 2 O. The sintered refractory products obtained from this green part give rise to a reduced bubbling effect.

1. A region of a glassmaking furnace comprising a sintered refractory product obtained by sintering a green part having the following average mineral chemical composition, in percentages by weight on the basis of the mineral oxides:
   40%≦Al 2 O 3 ,
 
   0%≦ZrO 2 ≦41%,
 
   2%≦SiO 2 ≦22%,
 
   1%<Y 2 O 3 +V 2 O 5 +TiO 2 +Sb 2 O 3 +Yb 2 O 3 . 
 
     
     
       2. The region according to  claim 1 , wherein said green part has the following average mineral chemical composition, in percentages by weight on the basis of the mineral oxides:
   40%≦Al 2 O 3 ≦94%,
 
   0%≦ZrO 2 ≦41%,
 
   2%≦SiO 2 ≦22%,
 
   1%<Y 2 O 3 +V 2 O 5 +TiO 2 +Sb 2 O 3 +Yb 2 O 3 . 
 
     
     
       3. The region according to  claim 1 , wherein the composition of said green part is such that, in percentages by weight on the basis of the mineral oxides:
   3%≦SiO 2 ≦22%.
 
 
     
     
       4. The region according to  claim 1 , wherein the composition of said green part is such that, in percentages by weight on the basis of the mineral oxides:
   TiO 2 ≧2%.
 
 
     
     
       5. The region according to  claim 1 , wherein the composition of said green part is such that, in percentages by weight on the basis of the mineral oxides:
   Y 2 O 3 +V 2 O 5 +TiO 2 +Sb 2 O 3 +Yb 2 O 3 ≦5%.
 
 
     
     
       6. The region according to  claim 1 , wherein the composition of said green part is such that, in percentages by weight on the basis of the mineral oxides:
   Y 2 O 3 +V 2 O 5 +TiO 2 +Sb 2 O 3 +Yb 2 O 3 >2%. 
 
     
     
       7. The region according to  claim 1 , wherein the green part is such that, in percentages by weight on the basis of the mineral oxides:
   Y 2 O 3 +V 2 O 5 +TiO 2 +Sb 2 O 3 +Yb 2 O 3 >3%. 
 
     
     
       8. The region according to  claim 1 , wherein the green part is such that, in percentages by weight on the basis of the mineral oxides, of at least one oxide from Y 2 O 3 , V 2 O 5 , TiO 2 , Sb 2 O 3 , and Yb 2 O 3  is greater than 1%. 
     
     
       9. The region according to  claim 1 , wherein the green part is such that, the content, in percentages by weight on the basis of the mineral oxides, of at least one oxide from Y 2 O 3 , V 2 O 5 , TiO 2 , Sb 2 O 3 , and Yb 2 O 3  is greater than 2%. 
     
     
       10. The region according to  claim 1 , wherein the green part is such that, the content, in percentages by weight on the basis of the mineral oxides, of at least one oxide from Y 2 O 3 , V 2 O 5 , TiO 2 , Sb 2 O 3 , and Yb 2 O 3  is greater than 3%. 
     
     
       11. The region according to  claim 1 , wherein the green part is such that in percentages by weight on the basis of the mineral oxides:
   Y 2 O 3 ≧1%.
 
 
     
     
       12. The region according to  claim 1 , wherein the green part is such that, in percentages by weight on the basis of the mineral oxides:
   Y 2 O 3 ≧2%.
 
 
     
     
       13. The region according to  claim 1 , wherein the green part is such that, in percentages by weight on the basis of the mineral oxides:
   Y 2 O 3 ≧3%.
 
 
     
     
       14. A process comprising at least the following successive steps:
 a) preparation of a green part having the following average mineral chemical composition, in percentages by weight on the basis of the mineral oxides:
   40%≦Al 2 O 3 ,
 
   0%≦ZrO 2 ≦41%,
 
   2%≦SiO 2 ≦22%,
 
 
 1%<Y 2 O 3 +V 2 O 5 +TiO 2 +Sb 2 O 3 +Yb 2 O 3 , said green part being obtained from a mixture of raw materials to which no Fe 2 O 3  has been added, but as an impurity in the raw materials, and to which has been added an amount of greater than 1% and of 5% or less of a constituent consisting of one or more of oxides selected from the group consisting of Y 2 O 3 , V 2 O 5 , TiO 2 , Sb 2 O 3 , and Yb 2 O 3 , in percentages by weight on the basis of the mineral oxides; 
 b) sintering said green part to obtain a sintered refractory product; and 
 c) employment of said sintered refractory product in a region of a glassmaking furnace for the manufacture of soda lime or extra white soda lime glass. 
 
     
     
       15. The process according to  claim 14 , in which, at step b), the green part is sintered at a temperature of between 1300° C. and 1500° C. 
     
     
       16. The process according to  claim 14 , in which at step b) the green part is sintered to form a refractory block. 
     
     
       17. The region according to  claim 1 , wherein said green part is in a form of a block. 
     
     
       18. The region according to  claim 1 , wherein in said green part Y 2 O 3 +V 2 O 5 +Sb 2 O 3 +Yb 2 O 3 >1%. 
     
     
       19. The region according to  claim 1 , wherein said green part is obtained by adding to a mixture of raw materials an amount greater than 1% of a constituent consisting of one or more oxides selected from the group consisting of Y 2 O 3 , V 2 O 5 , TiO 2 , Sb 2 O 3  and Yb 2 O 3 .